Session Abstracts
Saturday, March 18, 2000
Welcome
Stephanie Harlan, Boardmember, Association of Monterey Bay Area Governments; Councilmember, City of Capitola
Moderators:
Dr. Gregor M. Cailliet, Chair, Monterey Bay National Marine Sanctuary Research Activities Panel; Professor of Biology, Moss Landing Marine Laboratories
Dr. Steven Webster, Chair Monterey Bay National Marine Sanctuary Advisory Council; Senior Marine Biologist, Monterey Bay Aquarium
Something Fishy: Human Dimensions of Ecosystem Change in the Monterey Bay
Dr. Caroline
Pomeroy, Research Scientist Institute of Marine Sciences, University
of California Santa Cruz
Tim Thomas, Museum Historian/Director of Public Programs Maritime Museum,
Monterey, California
In 1880, to avoid a conflict with the newly arrived Genovese fishermen, Chinese fishermen began to fish squid at night in Monterey Bay. By doing so, they set in motion one of the most colorful and controversial fisheries in California's history. Fishermen and scientists alike have been chasing the elusive squid for over a century, each with their own agenda. Over that time, many diverse cultural groups have fished for this nocturnal mollusk, adapting technologies, practices and products to ever-changing environmental, market and political conditions. The history of the fishery and its changing character provide useful insights into ecosystem change in the Monterey Bay.
The Response of the Sanctuary's Pelagic Ecosystem to Climate Variability
Dr. Francisco Chavez, Associate Scientist Monterey Bay Aquarium Research Institute, Moss Landing, California
In order to understand how ocean ecosystems respond to climate variability we need to first determine what are and what leads to mean conditions. These requirements are best met with continuous sustained observations. Traditional ship-based process studies are inherently sporadic, and provide still 'snapshots' of ocean conditions. Our group has focused on dynamics and change, and attempted to observe the ocean at multiple temporal scales. In 1989 we began with small-scale biweekly cruises measuring physical, chemical and biological variables. This data set is now an invaluable, decade-long time series; it has allowed us to understand and document the interrelations between the variables that control phytoplankton production in Monterey Bay with observations over forty seasons, two El Niño's, one La Niña, and one decade of climate change. In 1992 we deployed 2 moorings which telemeter data to MBARI where it is automatically processed, plotted, and distributed on the World Wide Web. This has in part been a technology-development effort, but the moorings are able to collect data at many times the resolution of the biweekly cruises as well as partly eliminate the human element from the data collection process. Finally, in 1997 we expanded the spatial scale of our studies to include the California Current proper. The 'SECRET' cruise series now encompass 16, 1-week cruises from shore westward to about 300 km. Serendipitously, a very strong El Niño developed during 1997 and matured late in the year. A dramatic recovery that led to a cold La NiÒa condition began in late 1998. With the decade-long time series cruises, the moorings, and the SECRET cruises, we have been ideally positioned to document the effects of these phenomena off the central California coast. In this presentation the pelagic ecosystem and the causes for its biological richness are first reviewed. The focus is on the seasonal cycle. Interannual and decadal variability are then considered. The data show clear physical-biological coupling, with warmer conditions associated with reduced nutrients, centric diatoms, chlorophyll and primary production. These relations hold both seasonally, with fall and winter warmer than the spring and summertime upwelling period, interannually with El Niño warmer and La Niña cooler, and decadally, with sea surface temperature gradually rising and chlorophyll, primary production, centric diatoms and subsurface nitrate levels all decreasing over the ten-year study. During the decade of the 90's the Sanctuary's upwelling ecosystem has trended towards a less productive, more 'oceanic' condition.
Patterns in Benthic Communities Within the Sanctuary
Dr. Stacey Kim, Adjunct Professor Moss Landing Marine Laboratories, Moss Landing, California
Most of the ocean bottom is covered with muds and sands, which are inhabited by infaunal invertebrates and also demersal fishes. Knowledge of these widespread benthic communities generally decreases with water depth as the bottom becomes more difficult to observe, sample, and experimentally manipulate. In addition, the area of seafloor also increases with depth, so there is a much greater area to explore in deeper water. The present study is the first to sample benthic communities from the inner shelf to the deep slope, permitting ecological comparisons that have been difficult to make in the past because of differences in sampling techniques, sample processing, taxonomy, and data analysis and presentation. From the surf zone to 15 m, crustaceans were common; the deeper zone was dominated by polychaete worms. An unexpectedly diverse and abundant community was observed at the shelf-slope break (150 m); the occurrence of a diversity and density hot spot at a major geographic feature could stimulate a re-evaluation of the processes that regulate benthic diversity. An ampeliscid amphipod community was found at 700 m, in the middle of the oxygen minimum zone (OMZ). The ampeliscid community was similar to some polar and sub-polar benthic communities, and possibly reflects an underutilized food resource in this region. A peak in polychaete worm biomass at 1000 m, at the bottom of the OMZ, may also indicate a region with relatively high inputs of food to the sea floor. Though analysis of the samples is not yet complete, we have a tantalizing glimpse of singular patterns and a uniquely valuable data set for comparing ecosystems from shallow water across the continental shelf into bathyal depths.
High School Students as Advocates for Progressive Fisheries Management
Michael Guardino, Chemistry, Physics and Subtidal Ecology Teacher Carmel High School, Carmel, California
In order to take a more active role in their secondary science education and to become advocates for effective fisheries management, eighteen Carmel Adult School students became certified as SCUBA divers and employed the scientific method to identify a conservation issue in the MBNMS that they could investigate directly. They completed 200 research dives inside and adjacent to the Point Lobos Reserve in Carmel Bay and established a data base that describes the abundance, diversity, and age structure of resident fish populations. The students found significant differences between the assemblage of fishes at Whalers Cove and South Monastery Beach after completing site characterizations and analyses of sessile invertebrate life. Preliminary findings indicate that the establishment of Marine Protected Areas may become a viable method of progressive fisheries management for Sebastes species (rockfish) on the Pacific Coast.
Are Marine Mammals in Hot Water or Does Hot Water Affect Marine Mammals
Dr. Jim Harvey, Associate Professor Moss Landing Marine Laboratories, Moss Landing, California
Numerous marine mammal populations were exploited in the past and their numbers have made remarkable increases, however, some species have undergone dramatic decreases in recent years or have not recovered. The California sea lion, northern elephant seal, and gray whale have increased via protection and resource health, whereas the Stellar sea lion, Hawaiian monk seal, and some large baleen whales either have declined or not recovered because of human influences or changes in the oceanic systems. In this talk, I will review the history of representative marine mammal populations in the North Pacific, discuss the factors that effect population growth and health, and make some predictions on the possible effect of global changes on marine mammal populations.
The Sanctuary's Rich and Wonderful Rocky Intertidal: How Has It Changed and How Do We Know?
Dr. John Pearse, Research Professor of Biology Joseph M. Long Marine Laboratory, Institute of Marine Sciences, University of California Santa Cruz
The Monterey Bay region of California has been well known for the luxuriant life in the rocky intertidal for many years. Nineteenth century naturalists found it to be a productive collecting area, and the 20th century saw the proliferation of detailed naturalist guidebooks. Innumerable students at educational institutions around the Bay have been enthralled by the beauty of the rocky intertidal life, agreed by all to be among the richest in the world in terms of abundance and diversity. At the same time, the past two centuries have seen a proliferation of human activities detrimental to this life, including waste disposal, collecting, and perhaps trampling. Signs of deterioration were evident by the end of the 19th century, and became most conspicuous by the 1970s. Nevertheless, there have been few long-term studies designed to detect these changes. The few such studies done over the past 30 years do indicate that conditions are improving. But for the longer-term, we can only compare earlier descriptive studies with current conditions. These comparisons provide evidence of long-term changes which may not be directly related to local human activity. The only way to understand how the rocky intertidal biota is faring over time is with well-designed, long-term monitoring programs. Fortunately, these are now being established around the Bay so that by the end of the 21st century people will have a much better idea of the status of this precious living habitat.
Muddy Handprints: 10,000 Years of Human Environmental Change in the Elkhorn Slough
Mark Silberstein, Executive Director Elkhorn Slough Foundation, Moss Landing, California
Elkhorn Slough in the central Monterey Bay is a microcosm of coastal land uses seen throughout the United States. It has provided a living laboratory for studying ecological change since the 1920s when McGinitie did his pioneering ecological research in the slough. The recent ecological history of the slough, as with most of the coast, will be dependent on how we interpret and respond to the lessons of the past and apply current ecological understanding to managing natural resources.